Side by Side fragrances

I don't think testing a fragrance against another one is the best way to decide if I like something, but it is fun to do sometimes. What I noticed is that there can be two fragrances I think are similar, but when I put one on each hand, I find them very different. Then again, sometimes it is just fun to have two unlayered fragrances going at once. One on the back of each hand, so the sillage drift changes as my hands move. The best side by side I've done is YSL M7 on the back of one hand, and Keiko Mecheri Oliban on the back of the other. That blended Agarwood next to blended Olibanum was quite an experience.